In clinical diagnostics, the examination of blood samples or other samples of a bodily fluid, for example the interstitial fluid, affords the possibility of early and reliable detection of pathological states and the targeted and founded monitoring of body states. Medical diagnostics generally presuppose obtaining a blood or interstitial fluid sample from the patient to be examined. To this end, the skin is usually perforated, for example at the finger pulp or the ear lobe, using a sterile, pointy or sharp lancet in order to obtain a few microliters or less of blood for the analysis.
These days, the self-determination of blood glucose is a method of diabetes monitoring applied worldwide. Blood glucose equipment in the prior art generally has analysis equipment into which a test element (e.g. a test strip and/or a test tape) is inserted. The sample to be analyzed is applied to a test field (also referred to as an analysis zone in the following text) of the test element and possibly reacts in the test field with one or more reagents which are generally selected specifically for the analyte to be detected. By way of example, the reaction can be detected in an optical, in particular photometric, and/or electrochemical fashion.
For said evaluation, the prior art discloses different forms of test elements and test equipment which can be used or modified for the purpose of the present invention. It is possible to refer in particular to the detection reagents illustrated in these documents for the purpose of the present invention. By way of example, it is possible to use strip-like test elements as are described, for example, in the documents CA 2311496 A1, U.S. Pat. No. 5,846,838 A, U.S. Pat. No. 6,036,919 A or WO 97/02487, the disclosures of each of which are hereby incorporated by reference in their respective entireties. Test tapes, with a multiplicity of test fields or analysis zones positioned in series on a tape that is then wound up in a cassette and provided for use in analysis equipment, are further multilayered test elements known from the prior art. Such cassettes and analysis tapes are described, for example, in the documents DE 10332488 A1, DE 10343896 A1, EP 1 424 040 A1, WO 2004/056269 A1 and US 2006/0002816 A1, the disclosures of each of which are hereby incorporated by reference in their respective entireties.
However, when using test elements in practice, a number of technical problems occur which have to be overcome in many cases by complex instrumental solutions. For example, it is a problem that various test elements which can be used in an analysis system can have differences between them. For example, differences can emerge regarding the manufacturer and/or the manufacturing process, regarding the detection reagents used, regarding the analyte to be detected, regarding the analysis method and/or analysis system to be used, regarding the conditions in which the analysis is to be carried out, regarding the parameters and/or the algorithms for evaluating measurements, regarding the lot numbers, regarding lot-specific peculiarities, regarding the production process, regarding the number of analysis zones on a test element or the like. Such test element specific information or analysis zone specific information will also be referred to as “test element specific information” in the following text, with this term intending to comprise general information relating to a test element and/or an analysis zone of the test element and which can accordingly change from test element to test element, or even within a test element, for example from analysis zone to analysis zone. This can also comprise other information than that mentioned above.
Since manual input of such test element specific information is generally unacceptable or difficult for the patient, the prior art discloses various systems in which such test element specific information can be read automatically. Hence, for example, systems are known in which a calibration test element must first of all be entered into the analysis system. See, for example, US 2007/0273928 A1, the disclosure of which is hereby incorporated by reference herein in its entirety. Also known are systems in which a separate evaluation code is provided on the test elements and which is read by a separate reading unit. See, for example, U.S. Pat. No. 5,281,395, the disclosure of which is hereby incorporated by reference herein in its entirety. In addition to such code systems for individual test strips, codings for test tapes are also known in which a coding region on the test tape is provided at the beginning of a test tape, the former comprising at least one item of information. This coding region can, for example, be read by the detector which is also used for the optical measurement. See, for example, U.S. Pat. No. 5,077,010, the disclosure of which is hereby incorporated by reference herein in its entirety.
In addition to the test element specific information, the correct positioning of the test elements in the analysis systems also plays an important role in many cases. Additional sensors which monitor a correct positioning of the test elements are generally provided for this purpose. One example of such positioning employs a separate orientation field on the test element which can be used to determine whether the test strip was inserted into the analysis system correctly or upside down. See, for example, U.S. Pat. No. 6,335,203 B1, the disclosure of which is hereby incorporated by reference herein in its entirety.
However, the analysis systems disclosed in the prior art are in many cases afflicted with disadvantages for practical use, which in particular substantially increase the instrumental complexity of such systems. Thus, in many cases, as illustrated above, a separate sensor system is required for acquiring the test element specific information and/or for acquiring the tape positioning. Such a sensor system means additional complexity in terms of hardware and software, which increases the production costs of the analysis systems and can also significantly increase the weight and the installation space of such systems, which play an important role in the practical use in the daily diagnosis.
It is therefore an object of the present invention to provide an analysis system and a method for detecting at least one analyte in a sample which, at least as far as possible, avoids the disadvantages of the systems and methods known from the prior art. In particular, the instrumental complexity is intended to be decreased, and a system with a small installation space and a low weight is intended to be provided.